a. Field of the Invention
This invention relates in general to new and useful improvements in movable actuators for the outlet elements of containers. More specifically, it relates to a novel one-piece movable actuator of the dispensing type for use with a container for fluid. Such a movable actuator system, sometimes termed a closure or valve, is adapted for association with the neck or other outlet opening of a container, for use in containing, and in incrementally dispensing fluids from such a container. In one embodiment the actuator system is designed to be child resistant.
b. Discussion of the Prior Art
There are many types of potable and non-potable fluids which are distributed in containers. It is often desirable to be able to dispense such liquids from containers in controlled quantities from time to time. Typical examples of such potable fluids include water, wine, milk, fruit juices and so on. Typical examples of non-potable fluids include antifreeze, motor oil, household cleaners, pesticides, paint thinners, bleach, laundry detergents and so on. An important requirement for fluid dispensing system closures for containers is that the closure should be capable of being sealed fluid tight when it is not desired to dispense fluid from the container, while the same closure should also be readily adapted for the easy, but controlled, dispensing of fluids from the container.
In the past, one simple solution to the problem has been to provide the container with a dispensing outlet, such as a spout, which spout is in turn provided with a removable closure cap. This arrangement, although simple, has the disadvantage that the closure cap for the spout is often lost or misplaced. Such an arrangement has the further disadvantage that it does not allow for the convenient maintenance of the dispensing outlet in a constant gravity fed position. A second solution to the problem in the past has been the provision of a container closure with an internal valve construction. While such closures have sometimes been satisfactory for sealing containers, such container closures have usually been relatively complicated, multi-part, and costly to manufacture, and have therefore been unsuitable or undesirable for economical mass production and mass distribution.
A number of less complicated, less costly closure systems which include a one piece internal valve construction have been taught by the prior art. For example, U.S. Pat No. 3,120,908 discloses a one-piece resilient closure system for use with containers. The closure of this reference is generally in the form of a cap having an end wall with a depending skirt for engagement over the neck of a container to provide a seal between the closure and the container neck. The closure of this reference also includes a cylindrical plug which depends from the inner surface of the end wall. The plug is designed to be located concentrically within the neck of the container to form a releasable seal between the outer circumference of the plug and the inner circumference of the neck of the container. This sealing relationship between the plug and the neck of the container is formed by an upwardly facing circular seat on the outer circumference of the plug, which circular seat engages the inner circumference of a circular internal lip in the neck of the container to thereby form a seal which normally retains fluids within the container. When the end wall of the closure is depressed it moves the entire plug inward so that the circular seat is moved to a 360.degree. released, non-sealing position from the lip in the neck so that fluids can be dispensed from the container. The closure system of this reference is designed for use in a manner such that, in order to avoid leakage, the container is normally placed upwards, with the closure out of constant gravity fed contact with the fluid in the container, when it is not being used to dispense such fluids. The very fact that the plug is designed to move the entire 360.degree. circumference of the seat out of sealing contact with the internal lip of the container neck provides a large area for potential leakage between the plug and the lip. This makes the system undesirable for use with a container in which fluids are in constant gravity fed contact with such a closure seal. Indeed, study of this reference will show that the closure system is not suggested for use in constant gravity fed contact with fluids in the container, but rather is taught for use in a system in which the container is normally placed in an upright position, with the closure out of contact with the fluids in the container, when fluids are not being dispensed. It has now been determined that this requirement for being placed in an upright position is due, not only to the fact that the structure of the closure of this reference is designed for 360.degree. release of the seal, but is also due to the fact that the closure structure lacks means to assure that the seat on the plug within the neck of the container will be free of leakage over its entire 360.degree. circumference. One of the reasons that the closure structure of the reference lacks reliability as to leakage prevention is that the plug is a smooth right cylinder which lacks means for assuring either its own cylindrical shape, or shape retention for its circular facing seat. Additionally, the plug lacks means for continuously urging the facing seat on the plug against the lip in the neck of the container. This results in a plug structure which has both a limited ability to urge and flex its outer facing seat against the lip on the neck of the container, and a lack of assurance that the plug and facing seat will retain their shape. All of these factors effect the ability of the plug of this reference to maintain a tight closure with the lip on the neck of the container. For all of these reasons this simple prior art closure design is not completely desirable for use with a fluid container, especially not on one in which there is constant gravity fed contact and pressure between the fluid in the container and the closure, and in which controlled flow of fluid without leakage is desired.
Also in the prior art, U.S. Pat Nos. 3,400,866, and 3,443,728 describe one-piece dispenser closure valves in which the valve is opened by placing upward and outward pressure on an external tab.